title: High Resolution MMC Arrays for Low Energy Electron Capture Spectrum Studies
creator: Barth, Arnulf
subject: ddc-530
subject: 530 Physics
description: Neutrinos are the least understood particles within the Standard Model of particle physics (SM), and their absolute mass scale, as well as the number of neutrino flavors, is still unknown. Numerous experiments, such as the ECHo experiment utilizing metallic magnetic calorimeters (MMCs) employed at mK temperatures, and the BeEST experiments using superconducting tunnel junctions (STJs), seek to provide answers. Both experiments aim to measure low-energy electron capture (EC) processes of the isotopes Ho-163 and Be-7, respectively. In this thesis, three developments have been made which will contribute towards a better understanding of neutrinos. First, advancements have been achieved towards a wafer-scale implantation of Ho-163 within the ECHo experiment needed to reach the high statistics required for the ECHo-100k phase. Second, a Python library was developed to offer versatile tools for measurements performed using MMCs. Lastly, a 30-day measurement of the Be-7 EC process was conducted using ECHo-100k detector chips, selected for their high performance in previous experiments. This measurement revealed a broadening of the K-GS and L-GS lines to 5.8 eV and 8.4 eV, respectively, consistent with  observations from the BeEST experiment.
date: 2024
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/34457/1/2023_PhD_Barth.pdf
identifier: DOI:10.11588/heidok.00034457
identifier: urn:nbn:de:bsz:16-heidok-344571
identifier:   Barth, Arnulf  (2024) High Resolution MMC Arrays for Low Energy Electron Capture Spectrum Studies.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/34457/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng